PURPOSE: To obtain a magnetic recording/reproducing method to a photosensitive film to generate clocks stably even when the running speed of the film is changed and surely detect the data.

CONSTITUTION: When synchronizing clock signals are preliminarily recorded an equal distance to a magnetic track (magnetic layer) 1 of a film with one polarity, the clock signals are reproduced by a magnetic head 2 and compared with a predetermined comparing level, whereby recording clock signals are generated. Based on the signal delayed by a delay device 8 corresponding to the running speed of the film detected by a speed detector 9, the recording data is recorded to the magnetic track 1. At the reproducing time, the clock signals are reproduced by a comparator 5 from the reproducing current obtained from the magnetic track 1. The data is reproduced by detecting the signal obtained by a comparator 6 at a gate 7.